Modeling, Analysis, and Experimental Validation of Frequency Dividers with Direct Injection

Figure 7

Phase portrait of system (6) with 𝑏_in=40𝜇A/V², 𝑐_nl+𝑐_in=115𝜇A/V³, 𝑘=−0.6mA/V², 𝑅=1950Ω, and 𝑉_in=0.5V. (a) for 𝑎_nl+𝑎_in=−1.81mA/V and Δ_𝑛=0, (𝑉,𝜃)=(3.9V,0^∘) is a stable node with 𝜆_𝑎=−0.083 and 𝜆_𝑏=−0.763; (b) for 𝑎_nl+𝑎_in=0.53mA/V and Δ_𝑛=0.1, (𝑉,𝜃)=(1.02V,22.2^∘) is a stable node with 𝜆_𝑎=𝜆_𝑏=−0.202.

(a)

(b)